1. Field of the Invention
The present invention relates to the field of liquid crystal displaying techniques, and in particular to a backlight module and liquid crystal display device.
2. The Related Arts
The liquid crystal display device (LCD) is widely applied to various electronic devices, such as, computers, mobile phones, electronic dictionary and liquid crystal television because of the advantages of thin, light-weight, low energy-consumption and low radiation. In general, a liquid crystal display device mainly comprises a backlight module, a liquid crystal display panel, and a driving circuit wherein the backlight module is categorized as a direct-type back light module or an edge-type backlight module.
The light sources in the direct-type backlight module is arranged on the back plate in a matrix format, while the light sources in the edge-type backlight module is arranged on the side of the back plate and the light emitted by the light sources passes a light-guiding plate to obtain a planar light source. In the direct-type backlight module, the number of the light sources must be sufficient to achieve better luminance uniformity, In the edge-type backlight module, even though the number of light sources is lower, a light-guiding plate is required to uniformly diffuse the light emitted by the light sources to achieve better luminance uniformity. The high number of light sources of direct-type backlight module and the light-guiding plate in the light sources of edge-type backlight module both increase the cost of the backlight module.